Abstract: A high-coercivity neodymium-cerium-iron-boron permanent magnet has at least one of the following features: the area of grain boundary RE-rich phases in the magnet accounts for 4% or more of the area of a whole field of view; the grain boundary RE-rich phases in the magnet are fine and uniformly distributed; and the mean value of ratios of the area of block-shaped grain boundary RE-rich phases located at intersections of three or more main-phase grains to the total area of all the three or more adjacent main-phase grains in the vicinity is less than or equal to 30%. RE-rich phases in the magnet are continuously distributed along grain boundaries, thereby increasing the depth of diffusion of a diffusion source into the magnet, improve the uniformity of distribution of the diffusion source in the, and thus further improving the magnetic performance of the diffusion magnet.

Abstract: A neodymium-iron-boron magnet as well as a preparation method therefor and the use thereof are provided. The magnet contains main-phase grains having an R2(Fe,M)14B structure, and grain boundary phases. The grain boundary phases has two-grain grain boundaries between every two main-phase grains and triangular grain boundaries consisting of gaps among every three or more main-phase grains. M represents Cu, Ga, and/or Al, and R is at least one rare earth element including Nd. By means of regulating the component proportions of elements Cu, Ga, Al, etc, a distribution rule thereof in a magnet, and the grain sizes of grains, a magnet with high Br and Hcj can be obtained.

Abstract: A high-remanence neodymium-iron-boron magnet, and a preparation method and the use thereof are provided. The neodymium-iron-boron magnet has crystal grains with an R-T-B type compound as a main structure, and a grain boundary phase. By means of adjusting the proportional relation of elements such as B, Cu, Ga, RE and Ti, the neodymium-iron-boron magnet can achieve a relatively high main phase grain volume ratio and effectively restrain the proportion of a B-rich phase in the grain boundary phase, such that the magnet has relatively high Br, and also has both good Hcj and squareness performance.

Abstract: A high-coercivity Nd—Fe—B sintered magnet and a preparation method and use thereof are provided. The sintered magnet contains the following components in percentage by a mass: 100%: 26-37 wt % of R, R being at least one rare earth element including Nd; 0.07-0.23 wt % of Mn; 0.8-1 wt % of B; 0.5-4 wt % of M, M comprising Cu and/or Al, and at least one selected from Co, Ti, Ni, Zr and Ga; and the remaining being Fe. A Mn-containing auxiliary alloy powder is mixed with a Mn-free neodymium-iron-boron main alloy powder to prepare the Nd—Fe—B sintered magnet. The Mn-containing auxiliary alloy powder, also contains at least one of metals Cu and Al. Mn can replace a part of Fe in the main phase, so that the amount of solid solution of beneficial elements in grain boundaries in the main phase is reduced, and the coercivity is improved.

Abstract: An expandable sintered neodymium-iron-boron magnet, a preparation method, and an application are provided. The magnet has a sintered neodymium-iron-boron magnet and an expandable coating coated on the surface of the sintered neodymium-iron-boron magnet. The sintered neodymium-iron-boron magnet coated with the expandable coating is used to replace a conventional assembly method of an epoxy resin adhesive coating magnet and potting resin glue, so that the magnet coated with the expandable coating may be inserted into a magnetic steel groove. The irreversible expansion of the coating itself is used to fix the magnet in the magnetic steel groove. Meanwhile, the use of the expandable coating shortens the assembly time of motors and improves the assembly accuracy of the motors.

Abstract: An R-T-B based permanent magnet material, a preparation method therefor and use thereof are provided. The R-T-B permanent magnet material forms M oxides at the grain boundary triple point, such that oxygen is enriched at the grain boundary triple point, thereby accurately controlling the oxygen content in the magnet. The permanent magnet material and the preparation method of the present disclosure can prepare products with strong corrosion resistance under the condition of unchanged magnetic properties, and improve the formability in the pressing process, thereby improving the qualified rate of the products.

Abstract: A composition of heat-expandable microspheres and an application thereof are provided. The composition includes heat-expandable microspheres and a solvent. The particle size of the heat-expandable microspheres is 5 ?m?D?40 ?m, preferably 8 ?m?D?20 ?m. The thickness of the walls of at least 60% of the heat-expandable microspheres is ?5 ?m, preferably the thickness is ?3 ?m. The solvent at least comprises one organic solvent having a boiling point of above 220° C. A thermal expansion coating containing the composition has a stable structure, relatively high resistance to thermal shrinkage, relatively high mechanical strength and adhesion, can be applied in the fixation of high temperature resistant parts, and can maintain the bonding stability thereof when placed long-term in a high temperature environment (140-180° C.).

Abstract: Disclosed are a coating composition, a preparation method therefor and use thereof. The coating composition comprises a composition of at least 60% heat-expandable microspheres having a wall thickness of less than or equal to 5 ?m, a water-based thermoplastic resin, a water-based thermosetting resin, and a hot-melt filling resin. By means of the coating composition of the present invention, thin-shell spheres can be quickly softened and destroyed within a short time in the heat-expansion process, and with the volatilization of an organic solvent, the coating composition cross-links, on the surface and inside of the coating, with a resin matrix in the coating to form a cross-linked network structure, thus strengthening the gap support of the coating, and enabling the coating to achieve stepped expansion, and after expansion, some polymer materials wrap an airbag and harden to form a stable hollow structure.

Abstract: The permanent magnet comprises a main phase structure of R2T14B crystal grains, and R is a rare earth element; T comprises at least Mn, Fe, and optionally a transition metal comprising Co; B is boron; the permanent magnet further comprises Mn and heavy rare earth elements which are distributed in a grain boundary in a diffusion mode. The heavy rare earth element is selected from at least one selected from Dy, Ho and Tb. According to the rare earth permanent magnet prepared through the preparation method, more heavy rare earth elements can be diffused into the magnet core along the grain boundary, Hcj distribution of the permanent magnet is improved, and meanwhile the corrosion resistance and the mechanical property of the permanent magnet are improved.

Abstract: In one aspect, an apparatus includes: a volatile memory to store a dynamic portion of a hybrid generic attribute (GATT) database structure; and a non-volatile memory coupled to the volatile memory to store a static portion of the hybrid GATT database structure, where the volatile memory is to store an attribute index array to identify whether an attribute datum of the hybrid GATT database structure is stored in the volatile memory or the non-volatile memory.

Abstract: A method for producing a sintered R-iron (Fe)-boron (B) magnet, the method including: (1) producing a sintered magnet R1-Fe—B-M, where R1 is neodymium (Nd), praseodymium (Pr), terbium (Tb), dysprosium (Dy), gadolinium (Gd), holmium (Ho), or a combination thereof; M is titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), cobalt (Co), nickel (Ni), gallium (Ga), calcium (Ca), copper (Cu), Zinc (Zn), silicon (Si), aluminum (Al), magnesium (Mg), zirconium (Zr), niobium (Nb), hafnium (Hf), tantalum (Ta), tungsten (W), molybdenum (Mo), or a combination thereof; (2) removing oil, washing using an acid solution, activating, and washing using deionized water the sintered magnet, successively; (3) mixing a superfine terbium powder, an organic solvent, and an antioxidant to yield a homogeneous slurry, coating the homogeneous slurry on the surface of the sintered magnet; and (4) sintering and aging the sintered magnet.

Abstract: A method for producing a sintered R-iron (Fe)-boron (B) magnet, the method including: (1) producing a sintered magnet R1-Fe—B-M, where R1 is neodymium (Nd), praseodymium (Pr), terbium (Tb), dysprosium (Dy), gadolinium (Gd), holmium (Ho), or a combination thereof; M is titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), cobalt (Co), nickel (Ni), gallium (Ga), calcium (Ca), copper (Cu), Zinc (Zn), silicon (Si), aluminum (Al), magnesium (Mg), zirconium (Zr), niobium (Nb), hafnium (Hf), tantalum (Ta), tungsten (W), molybdenum (Mo), or a combination thereof; (2) removing oil, washing using an acid solution, activating, and washing using deionized water the sintered magnet, successively; (3) mixing a superfine terbium powder, an organic solvent, and an antioxidant to yield a homogeneous slurry, coating the homogeneous slurry on the surface of the sintered magnet; and (4) sintering and aging the sintered magnet.

Abstract: A method for preparing an R—Fe—B based sintered magnet, including: preparing a R1—Fe—B-M sintered magnet having a thickness of between 1 and 10 mm; spraying a layer of Tb or Dy having a thickness of between 10 and 200 ?m on each surface of the sintered magnet in a sealed box under an Ar atmosphere by hot spraying method; and transferring the sintered magnet coated with the layer of Tb or Dy to a vacuum sintering furnace, heating the sintered magnet at the temperature of between 750 and 1000° C. in a vacuum condition or under the Ar atmosphere, and allowing heavy rare earth element Tb or Dy to enter an inner part of the sintered magnet via grain boundary diffusion.

Abstract: A method for preparing an R—Fe—B based sintered magnet, including: preparing a R1—Fe—B-M sintered magnet having a thickness of between 1 and 10 mm; spraying a layer of Tb or Dy having a thickness of between 10 and 200 ?m on each surface of the sintered magnet in a sealed box under an Ar atmosphere by hot spraying method; and transferring the sintered magnet coated with the layer of Tb or Dy to a vacuum sintering furnace, heating the sintered magnet at the temperature of between 750 and 1000° C. in a vacuum condition or under the Ar atmosphere, and allowing heavy rare earth element Tb or Dy to enter an inner part of the sintered magnet via grain boundary diffusion.

Abstract: A neodymium-iron-boron (NdFeB) magnet having gradient coercive force and its preparation method are disclosed. The NdFeB magnet includes at least two NdFeB material layers having different coercive force, including an exterior layer having high coercive force and at least a medial layer having low coercive force. The exterior layer is connected to the medial layer via a sintered layer along an orientation direction. The NdFeB magnet has high magnetic properties and high resistance to magnetism loss.